Dictionary Definition:
aru m. the sun L
• the redblossomed Khadira tree L
• for arus n. only in comp. with -ṃ-tuda mf(ā)n. (Pāṇ. 3-2, 35 and vi, 3, 67) 'beating or hurting a wound', causing torments, painful Mn. ii, 161, &c
aru and s.v